Exam2

Potential Exam 2 Questions

1. Which of the following Toll Like Receptors are responsible for the recognition of Bacterial cell envelope features
a. TLR-4
b. TLR-5
c. TLR-3
d. TLR-9
answer: a and b

2. What are the similarities of a TLR and NOD?
a. TLR's contain leucine rich repeats.
b. NOD's recognize microbial motifs intracellularly
c. TLR's are preferentially located on professional phagocytes or dendritic cells
d. NOD's are located on the intracellular and extracellular surfaces
answer: a, b, and c
__Wouldnt answer b be incorrect here…because TLRs interact with molecular motifs extracellularly?
no, there are TLR's (3,7,8,9) that recognize microbial parts inside the cell once the phagosome has beat the crap out of the microbe

Wouldn't answer C be wrong also since NOD1 are found on all cells and nod 2 are on professional phagocytes?
3. What are the differences of MyD88 and TRIF?
a. TRIF is a signal transduction protein
b. MyD88 interacts with TLR-4.
c. TRIF is only binded by TLR-3
d. Conformational changes of MyD88 by TLR-4 causes a phosphorylation cascade
answer: c

Wouldn't c be wrong since Trif can bind to TLR-3 and TLF-4, I think you meant to say only TRIG bins to TLR-3
What is TRIG?

4. Transcription activation by NF-kappa B causes:
a. neutrophils to exit the signaling site
b. endothelia to become "stickier"
c. vascular permeability to decrease
d. the release of acute phase proteins in the liver
answer: b, d
5. What are some functions and/or features of M. tuberculosis that protect it from being killed by a phagolysosome
a. Mycolic Acid
b. Produces Catalase
c. Stops phaolysosome formation
d. Lowers the negative charge on its membrane
e. Produces a biofilm
answer: a,b,c

6. Have an exact question from exam 1 and have it made extra credit!!!!!
This would make it way to easy!

7. What are similarities between ROS and iNOS?
a. ROS denatures proteins and damages bases of DNA
b. iNOS is turned on by phagocyotsis
c. ROS leads to the creation of free radicals
d. ROS contain NADPH oxidase
answer: a, c
A would not be right here because iNOS is the enzyme that makes Nitric Oxide. Nitric Oxide denatures proteins and damages DNA, not iNOS

8. Put the steps to signal transduction in order
a. Conformational change of TLR
b. Change in interaction btw cytoplasmic proteins & intracellular domain of TLR
c. Binding of microbial product to extracellular domain of TLR
d. Expression of inflammatory cytokine genes
e. Change in shape of intracellular domain
answer: c,a, e, b, d

9. Name a disease that has to do with malfunctioning NOD's and briefly explain it
answer:
Crohn's disease is chronic bowel inflammation. It is correlated with mutations of NOD's so cells are unable to respond to peptidoglycan.
or……..
Blau Syndrome is chronic organ inflammation. NOD's are always expressed, so the concentration of them is too high.

10. What is true about imflammatory cytokines?
a. they are released in response to steroid hormones
b. IL-10 is an inflammatory cytokine
c. some increase vascular permeability
d. IL-1 allows the release of IL-8, which attracts neutrophils
e. IL-6 triggers release of acute phase proteins from the liver
f. TGF-beta resets the hypothalamus
answer: c, d, e

11. Bonus what are Dx. RR favorite two diseases? :)
a. Mycolic tuberculosis
b. Crohn’s disease
c. Blau syndrome
d. Black plague

12. what are examples of professional phagocytes
a. neutrophils
b. dendritic cell
c. macrophages
d. epithelial cells
answer :a,b,c

13. What are the difference between reactive oxygen species and reactive nitrogen species?
a. NADPH creates reactive Oxygen intermeidates
b. iNOS creates reactive oxygen intermediates
c. Only ROS are used to attack bacteria.
d. Both ROS and RNS are used to kill bacteria.
answers: A

14. Put the events of phagocytosis in order.
a.Phagolysosome formation
b. Binding of receptors
C. actin polymerization
Answer: b,c,a

15. What are the differences between primary and secondary granulous.
a. primary granules are used to kill bacteria
b. primary granules use BPI to poke wholes in bacteria
c. secondary granules denature bacteria proteins
d. secondary use defensins and cathlicidans.
answers: b,c

16. What are the differences between NOD1 and NOD2
a. NOD1 is a cytoplasmic protein
b. NOD2 recognizes components present in both gram (+) and gram (-) bacteria
c. NOD2 is found on many different types of cells
d. NOD1 recognizes components only present in gram (-) bacteria

17. Draw a gram (-) bacterium, label the conserved components recognized by the immune system, and include which TLR would recognize each component.

18. Lipopolysaccharide (LPS), a major component of the cell wall of Gram-negative bacteria, is the principal ligand for:
a. TLR2
b. TLR3
c. TLR4
d. TLR5
answers: c

19. The TLRs that are localized to internal membrane-bounded compartments such as the phagosme are those that recognize:
a. lipoproteins and lipoteichoic acid
b. double-stranded RNA (dsRNA)
c. CpG-containing DNA
d. flagellin
answers:b, c

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